Breakthrough Sensitivity and Robustness for PFAS Analysis in Chicken Tissue for EPA Method 1633A

Importance of the Topic

Per- and polyfluoroalkyl substances (PFAS) are persistent synthetic chemicals with widespread industrial and consumer uses. Their environmental stability and bioaccumulation potential pose serious health and regulatory concerns. Reliable, sensitive, and robust analytical methods are critical to detect trace PFAS in complex biological matrices, such as chicken tissue, to support regulatory compliance (EPA Method 1633A) and protect public health.

Objectives and Study Overview

This study evaluates the performance of the Shimadzu LCMS-8065XE triple quadrupole mass spectrometer combined with automated sample extraction for quantitative PFAS analysis in chicken tissue. Key aims include:

• Meeting EPA Method 1633A limits of quantification (LLOQ) for 40 target PFAS compounds
• Achieving chromatographic separation of PFOS from interfering bile acids
• Demonstrating method robustness over one week and more than 900 injections

Methodology and Instrumentation

Sample Preparation and Extraction:

• Approximately 2 g chicken tissue spiked with native PFAS and internal standards
• Automated solid-phase extraction (SPE) using the EDGE PFAS system and Supelclean ENVI-WAX cartridges
• Conditioning, loading, washing, elution, and cleanup steps optimized for PFAS recovery

Calibration Standards:

• Native PFAS targets: 2.5–62 400 ng/L
• Extracted internal standards: 1.0–20 µg/L
• Non-extracted internal standards: 1.0–4.0 µg/L

Instrumentation:

• UHPLC: Shimadzu Nexera X3/40 with Shim-pack Scepter C18 columns and delay column to reduce background
• Mass Spectrometry: Shimadzu LCMS-8065XE, triple quadrupole
• LC conditions: 0.3 mL/min, 10 min run, mobile phases: 2 mM ammonium acetate (A), acetonitrile (B)
• MS conditions: Nebulizing gas 1.1 L/min, heating gas 15 L/min, drying gas 5 L/min, interface 225 °C, DL 200 °C, heat block 250 °C, negative mode

Main Results and Discussion

Limits of Quantification and Sensitivity:

• Achieved up to 80-fold lower LLOQ than EPA 1633A requirements
• All 40 PFAS quantified with RSE between 3 % and 17 %
• Calibration curves linear with R² > 0.995 across at least seven concentration levels

Chromatographic Separation:

• Resolved PFOS from taurodeoxycholic, taurochenodeoxycholic, and tauroursodeoxycholic acids by ≥ 1.5 min
• 10 min total analysis time meets EPA method requirements

Robustness:

• Over 900 continuous injections spanning seven days retained CCV accuracies within 70–130 %
• No instrument downtime or cleaning required during robustness test

Benefits and Practical Applications

The optimized method delivers:

• Superior sensitivity for low-level PFAS monitoring in food and biological samples
• High throughput with 10 min runs and automated extraction
• Reliable performance for routine environmental and regulatory laboratories (QA/QC, food safety)

Future Trends and Applications

Prospective developments include:

• Extension to other tissue and environmental matrices
• Integration of high-resolution mass spectrometry for non-target PFAS screening
• Miniaturized and field-deployable extraction devices
• Machine-learning algorithms for automated data processing and anomaly detection
• Method adaptation for emerging PFAS classes and regulatory updates

Conclusion

The Shimadzu LCMS-8065XE combined with automated EDGE PFAS extraction meets and exceeds EPA Method 1633A requirements for PFAS analysis in chicken tissue. The method achieves exceptional sensitivity, rapid throughput, robust calibration stability, and clear chromatographic separation of critical analytes and interferences. It is well suited for routine monitoring in research, industrial, and regulatory laboratories.

Instrument Used

• Shimadzu LCMS-8065XE triple quadrupole mass spectrometer
• Shimadzu Nexera X3/40 UHPLC system
• Supelclean ENVI-WAX SPE cartridges
• EDGE PFAS automated extraction system (CEM)

References

1. EPA Method 1633A, Analysis of Per- and Polyfluoroalkyl Substances (PFAS) in Aqueous, Solid, Biosolids, and Tissue Samples by LC-MS/MS